package com.hjp.designmode.strategy.utils;

import cn.hutool.core.codec.Base64Decoder;
import cn.hutool.core.codec.Base64Encoder;
import lombok.extern.slf4j.Slf4j;

import java.io.UnsupportedEncodingException;

/**
 * @Description: 过滤emoji表情与非emoji表情
 * @Author: huangjp6
 * @Date: 2022/4/2 16:27
 */
@Slf4j
public class EmojiFilter {
    /**
     * 检测是否有emoji字符
     *
     * @param source 需要判断的字符串
     * @return 一旦含有就抛出
     */
    public static boolean containsEmoji(String source) {
        int len = source.length();
        for (int i = 0; i < len; i++) {
            char codePoint = source.charAt(i);
            if (!notisEmojiCharacter(codePoint)) {
                //判断确认有表情字符
                return true;
            }
        }
        return false;
    }

    /**
     * 非emoji表情字符判断
     *
     * @param codePoint
     * @return
     */
    private static boolean notisEmojiCharacter(char codePoint) {
        return (codePoint == 0x0) ||
                (codePoint == 0x9) ||
                (codePoint == 0xA) ||
                (codePoint == 0xD) ||
                ((codePoint >= 0x20) && (codePoint <= 0xD7FF)) ||
                ((codePoint >= 0xE000) && (codePoint <= 0xFFFD)) ||
                ((codePoint >= 0x10000) && (codePoint <= 0x10FFFF));
    }

    /**
     * 过滤emoji 或者 其他非文字类型的字符
     *
     * @param source 需要过滤的字符串
     * @return
     */
    public static String filterEmoji(String source) {
        if (!containsEmoji(source)) {
            return source;
        }

        StringBuilder buf = null;//该buf保存非emoji的字符
        int len = source.length();
        for (int i = 0; i < len; i++) {
            char codePoint = source.charAt(i);
            if (notisEmojiCharacter(codePoint)) {
                if (buf == null) {
                    buf = new StringBuilder(source.length());
                }
                buf.append(codePoint);
            }
        }

        if (buf == null) {
            return "";//如果没有找到非emoji的字符，则返回无内容的字符串
        } else {
            if (buf.length() == len) {
                buf = null;
                return source;
            } else {
                return buf.toString();
            }
        }
    }

    public static void main(String[] args) {
        String str = "\uD83E\uDD35\u200D♂⏰\uD83C\uDF4E\uD83C\uDF1F\uF8FF";
        try {
            byte[] bytes = str.getBytes("utf-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        log.info("utf-8 ok");
        boolean b = EmojiFilter.containsEmoji(str);
        System.out.println(b);
        String encode = Base64Encoder.encode(str.getBytes());
        log.info("encode=" + encode);
        String decodeStr = Base64Decoder.decodeStr(encode);
        log.info("decodeStr=" + decodeStr);
        String str1 = "⏰";
        boolean b1 = EmojiFilter.containsEmoji(str1);
        System.out.println(b1);
    }
}